Within the Public Switched Telephone Network (PSTN), some subscribers are served by Digital Loop Carrier (DLC) systems which connect subscribers to a central office (CO) voice switch via efficient high speed digital connections. The path of a telephone call in a universal type DLC system requires that the signal intended for a particular subscriber must pass through one digital to analog (D/A) conversion at the voice switch, one analog to digital (A/D) conversion at the central office terminal (COT) and another D/A conversion at the remote data terminal of the universal type DLC system.
The rapid growth of Internet usage has resulted in the desire for faster data transmission. Modem technology has advanced to provide users with the ability to receive data at a rate of 56 kilo bits per second (56K). An example of such technology being standardized by the International Telecommunications Union as V.PCM type modems. This rate is desirable because of the increased amount of information available via the Internet. However there exists competing technologies attempting to become the industry standard for 56K transmissions. All these competing technologies rely on the return path modem signal traversing one D/A converter and one A/D conversion at a subscriber's receiver. Thus, 56K modem technology is available to most telephone subscribers except those served by Universal type DLC systems. This is due to the additional D/A and A/D conversions between the voice switch and the COT.
U.S. Pat. No. 5,610,910 entitled "Access to Telecommunications Networks In Multi-Service Environment" ("the '910 patent") describes a system which utilizes a CPE connector and a module to route traffic from customer premise equipment (e.g. a computer, fax machine or telephone) to one or more networks (e.g. PSTN, data, etc.). However, the module disclosed in the '910 patent decodes the received signal and analyzes the contents of the data to identify the network service requested (i.e. which ISP). The request must be reassembled (e.g. address conversion, rerouting, etc.) before re-transmitting it to the desired destination network. These additional steps compromise transmission time and provide unwanted data conversions.
Thus, there is a need to provide Universal DLC subscribers with the capability to use 56K modem service.